Some drug price-control advocates say recent moves by big pharmaceutical companies to buy smaller biotechnology companies that have developed specialty drugs are contributing to rising drug costs and a lack of transparency around how those drugs are priced -- though others say such a business model has been common for years, and the recent high-profile acquisitions by Roche and Gilead Sciences simply serve to highlight this model. FDA's approval of drug maker giant Roche's $94,000 a year drug for a...